Trunked radio frequency (RF) or wireless communication systems for radio communication devices are well known in the art. Typically in such systems, a plurality of radio communication devices (e.g. two-way radios) share a limited number of communication resources, e.g. one or more repeater stations and communication channels. Wireless communication systems employing TDMA signaling are well known. These systems divide a RF resource into a series of recurring time frames which are further divided into timeslots and can be shared by communication devices or talkgroups of such radio communication devices. These timeslots, occurring periodically in time frames, constitute the communication channels (timeslots) of interest.
In one approach to sharing timeslots or channels, the timeslots or channels are typically assigned to requesting radio communication devices by a communication resource controller coupled to the repeater stations, which requests and assignments are exchanged via a common control channel. The controller might assign a timeslot to a radio communication device for a single transmission such that, at the end of the radio communication device's transmission, the timeslot (channel) is re-assigned to another radio communication device (i.e. so-called transmission trunking).
In one alternative approach, the controller might assign a timeslot (channel) to a group of radio communication devices for engaging in a conversation, and keep the timeslot (channel) assigned to the group until completion of, or a substantial pause in, the conversation. That is, the assigned timeslot (channel) is not made available for re-assignment until the end of the conversation is anticipated. A conversation may include multiple transmissions from multiple radio communication devices in a talkgroup and is referred to in the art as a message. Accordingly, this form of timeslot (channel) assignment is referred to as message trunking.
The above known timeslot (channel) assignment approaches require a common controller (system level controller) to monitor timeslots (channels) and determine when to assign, maintain assignment, deassign and reassign timeslots (channels) to a talkgroup or a radio communication device. Thus, known timeslot (channel) assignment approaches use common or system level controllers and can cause communication delays and may be an unnecessary or undesirable overhead for wireless communication systems.
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